ORA-01810: format code appears twice
Oracle PL/SQL error message: ORA-01810: format code appears twice.
Cause:
A format code was listed twice in a date specification. Each format code may be specified only once in the function TO_DATE.
Solution:
Remove the duplicate format code from the date specification, then retry the operation.
Example:
SELECT TO_DATE('2015.12.28','YY YY/MM/DD') FROM dual;
Output:
ORA-01810: format code appears twice
Correct:
SELECT TO_DATE('2015.12.28','YYYY/MM/DD') FROM dual;
Output:
28-DEC-2015 00:00:00